Containers for storing food are well known in the art. It is well known that such containers may be produced from many different materials and combinations of materials, e.g., paperboard, glass, aluminum and certain plastics. There are, of course, advantages and disadvantages which inhere in the use of each of those different materials. For example, paperboard is a relatively strong container material but suffers from the disadvantage that it is relatively permeable to gases and, therefore, foods stored in containers constructed solely from paperboard lose their freshness at a relatively rapid rate. On the other hand, glass, aluminum and some plastic materials are relatively impermeable to gases, but to obtain sturdy containers from those materials is expensive because of the relatively high cost of those materials.
It is therefore most desirable in the food container art to provide a container which is sturdy, relatively impermeable to gases and relatively inexpensive. The containers of the present invention satisfy each of those three criteria.
The present invention is also directed to a process and apparatus for making that sturdy, relatively impermeable and inexpensive container.